Pre-tensioned fully flexible troughing idler assembly



Aug. 25, 1964 R. F. LO PRESTl 3,145,330

FREE-TENSIONED FULLY FLEXIBLE TROUGHING IDLER ASSEMBLY Filed March 5, 1962 2 Sheets-Sheet 1 INVENTOR.

Aug. 25, 1964 R, F. L0 PRESTI 3,145,830

PRE-TENSIONED FULLY FLEXIBLE TROUGHING IDLER ASSEMBLY Filed March 5, 1962 2 Sheets-Sheet 2 g a 2/ 7/ 9n INVENTOR.

7 Fa Fla/371k .z l 49 BY PzmQr 67/2 62" United States Patent 3,145,830 PRE-TENSIONED FULLY FLEXIBLE TROUGHING IDLER ASSEMBLY Roy F. Lo Presti, Chicago, Ill., assignor to Goodman Manufacturing Company, Chicago, Ill., a corporation of Illinois Filed Mar. 5, 1962, Ser. No. 177,381 11 Claims. (Cl. 198-192) This invention relates to idler assemblies for belt conveyors, and particularly to an improved troughing idler assembly which retains the shock absorbing and belt training features of prior idler assemblies, yet is much lighter and equally strong.

This application is a continuation-in-part of my copending application, Serial No. 80,869, filed January 5, 1961, now Patent Number 3,109,534.

Accordingly, a primary object of the invention is to provide a troughing idler assembly which is considerably lighter in weight than prior idler assemblies, yet retains all of the desirable characteristics of prior idler assemblies, including longitudinal and vertical impact absorption, excellent belt training characteristics, ease of installation and maintenance, and low cost.

Another object is to provide a troughing idler assembly in which the individual roller and roller shaft assem blies are inherently less susceptible to damage.

Yet another object is to provide a troughing idler assembly in which the roller shafts in the end rollers of a multiroller troughing assembly are placed under tension prior to installation, thereby increasing the inherent resistance of the shaft to impact loads by utilizing the inherent strength of the roller shaft material.

A further object is to reduce the overall weight of an at least partially frame supported troughing idler assembly by utilizing smaller members for structural support of the rollers in conjunction with tensioned roller shafts.

Yet a further object is to provide a troughing idler assembly in which the load absorbing and transmitting members of the assembly are operable immediately upon imposition of loads.

Yet another object is to accomplish all of the foregoing objects without increasing the size, or weight, of present troughing idler assembly components, particularly the roller shaft.

Yet a further objects is to provide a method of increasing the carrying capacity of a carrying idler and a wire rope sideframe conveyor.

Yet a further object is to provide a wire rope sideframe conveyor in which the transverse pull of the wire ropes at least partially counteracts a preloaded portion of each wing roller frame supporting structure to thereby increase the carrying capacity of the troughing idler assembly of which the wing roller assemblies are components.

Other objects and advantages of the invention will become apparent upon reading the following description of the invention.

The invention is illustrated more or less diagrammatically in the accompanying figures.

FIGURE 1 is a front elevation of a troughing idler assembly constructed in accordance with the principles of the present invention;

FIGURE 2 is a top plan view with the belt omitted of the troughing idler assembly of FIGURE 1;

FIGURE 3 is a partial sectional view taken substantially along the line 3-3 of FIGURE 2;

FIGURE 4 is a sectional view taken substantially along the line 44 of FIGURE 3',

FIGURE 5 is an end view of the troughing idler assembly;

FIGURE 6 is a sectional view taken substantially along the line 6-6 of FIGURE 5; and

3,145,830 Patented Aug. 25, 1964 FIGURE 7 is a sectional view taken substantially along the line 77 of FIGURE 3.

Like reference numerals will be used to refer to like parts throughout the following description of the drawings.

A troughing idler assembly of the general type illustrated in the Craggs et al., Patent 2,773,257 is shown in FIGURE 1. The troughing idler assembly is composed of a plurality of roller assemblies 10, 11 and 12, which in this instance are serially arranged, though it will be understood, as will more fully appear, that the rollers need not invariably be serially arranged. The rollers in turn support the carrying reach 13 of a flexible conveyor belt. The entire troughing idler assembly is connected by suitable structure, which will be later described, to a pair of wire ropes 14 and 15 of a wire rope side frame conveyor. It will be understood that the wire ropes are supported at suitable intervals along a conveying course by support structure which maintains the ropes generally parallel to one another at any given point along the course, and substantially equally spaced at the support locations. For a fuller description of exemplary support structures and a broad description of the conveyor, reference is made to the aforementioned Craggs et al. patent.

Roller assemblies 10 and 12 are substantially identical and a description of one will suflice for both.

Roller assembly 10 includes a roller 16 which is mounted by suitable bearings, not shown, for rotation about a dead shaft 1'7 which extends the length of the roller shell. The roller shell may be of any convenient diameter, for example 2 /2 inches up to 5 inches or more, the invention not being limited to any particular roller size.

The inner end 18 of the shaft is connected by pivot pin 19 to a generally upstanding support structure indicated generally at 20. As best shown in FIGURE 4, the support structure comprises a pair of plates or bracket members 21, 22, each of which is welded at its lower edge and end, as at 23, 24, to an elongated bodily resilient frame member 25. Frame member 25 in this instance is round, as best seen in FIGURES 4 and 7, but it will be understood that within the scope of the invention a suitable structural shape may be utilized. The primary requirements of the elongated frame member are that it be bodily resilient in the sense that it have at least a limited range of elasticity similar to the well known elastic limit range of steel. It will also be noted that the frame 25 may advantageously be of a size substantially equal to the roller shaft 17. In other words, the weight per unit length of the frame member 25 may advantageously be on the order of that of the roller shaft 17.

The outer portion 30 of frame member 25 is welded along its longitudinal diamensions to a pair of side plates 31, 32. The inner ends of the plates are bent toward one another and welded to an overlapping portion of the frame member 25, and the outer ends are welded to an L-shaped supporting member 33, as best seen in FIG URE 4. Generally horizontal leg 34 of member 33 is welded at its end to the outer end of frame member 25, as best seen in FIGURE 4. A rectangular slot 35 is formed in that portion of the generally horizontal leg 34 adjacent the generally vertical portion of the member, as best seen in FIGURES 3 and 4. Although a rectangular slot has been shown, any suitable configuration may be utilized within the scope of the invention as will appear hereinafter.

A roller shaft extension member, indicated generally at 45, includes a clevis 46 at its inner end which is pivotally connected as at 47 to the outer end of the roller shaft 17. The outer end of extension 45 is threaded as at 48 and receives a tightening nut 49.

A serrated generally horizontally disposed training slot 50 is formed in the generally upstanding leg 38 of member 33. The slot comprises three overlapping holes which provide three seats 51, 52 and 53 as best seen in FIGURE 5. The inner edge of nut 49 is rounded, as at 54, to seat in whichever training seat 51, 52 or 53 is selected.

Roller assembly is connected to the balance of the roller assemblies by another pivot pin 55 which connects the adjacent end of dead shaft 56 of intermediate roller 57 to support structure 20. Although in this instance a pair of wing roller assemblies 10 and 12 and one 1nte rmediate roller assembly 11 have been illustrated, 1t Wlll be understood that within the scope of the invention a greater or lesser number of intermediate roller assemblies may be utilized. The illustrated number is merely for convenience of description.

Left roller assembly 10 is connected to wire rope 14 means of rope clamp assembly 60 and shock link 61.

The rope clamp 60 consists essentally of an elongated generally U-shaped plate 62, the bight of which forms a seat for the wire rope. A pair of wedges 63, 64, which pass through aligned apertures in the upper and lower legs or flanges of the plate force the wire rope into snug engagement in the seat.

The shock link consists essentially of upper and lower plates 65, 66 and a pair of pins 67, 68 connecting the lmk plates. Pin 67 passes through the left or outer end of lower link plate 66, an aperture in the upper leg of plate 62, a spacing washer 69 and upper link plate 65. Spacing washer 69 is of a thickness approximately equal to that of generally horizontal leg 34 of supporting member 33.

Inner pin 68 passes upwardly through lower link plate 66, a second spacing washer 70, leg 34 of member 33 and upper link plate 65. Spacing washer 70 is of a thickness on the order of the thickness of the upper leg of plate 62. It will thus be seen that the spacing washers 69, 70 maintain the link plates 65 and 66 substantially parallel to one another. Likewise, the two link plates, leg 34 and the upper flange of clamp plate 62, are malntarned parallel to one another so that they slide with respect to one another in generally parallel planes.

The ends of the upper flange of rope clamp 60 are raised, as at 71, 72, to provide stops for the longitudinal movement of roller assembly 16.

The use and operation of the invention are as follows:

Before installing the troughing idler assembly in a wire rope sideframe conveyor, nut 49 is tightened until dead shaft 17 is placed in tension. Simultaneously, frame member 25 deforms slightly due to the inherent resiliency of its material. The amount of deformation may be very slight. Relative deformation is diagrammatically shown in FIGURE 3 in which the line 73 represents the normal, unstressed position of the upper surface of member 25. The space between line 73 and the upper solid outline of member 25 represents the deflection.

To install a troughing idler, the Wire ropes 14 and are drawn together by any suitable means well known in the art. Generally, prior to drawing the ropes together, one end of the troughing idler assembly, such as the end illustrated in FIGURE 3, is placed over wire rope 14, and then after the ropes are drawn together the other end of the assembly is slipped over wire rope 15. Since the tension in wire ropes 14 and 15 may be quite high, for example on the order of 1,000 to 2,500 pounds per wire rope, there will be a considerable resistance to transversely directed deflection of the strands. The term transverse in this application is used as measured with respect to the axis of the wire ropes or, perhaps more accurately, the longitudinal axis of the conveyor. In any event, once the troughing idler assembly is placed on the Wire ropes, the restraining force is removed and the ropes are free to move back to their normal positions. Since they exert an outward pull on the assembly, they will tend to counteract the deflection in frame member 25. The net result is that at least a portion of the deflection imparted to frame member 25 by tightening nut 49 is counterbalanced.

The placing of the roller shaft 17 in tension results in several unexpected advantages.

In the first place, a very rigid structure, consisting of the dead roller shaft, shaft extension 46, member 38, resilient bar 25 and support structure 20, is formed. This particular structure is considerably stronger than the conventional cradle structure in which the roller shaft is under no tension. As a result, the amount of load that the frame member 25 is required to carry is considerably lessened and it may, therefore, be made much lighter than the present structure. In one commercial embodiment, the member corresponding to frame member 25 has been made of inch x 3 /2 inch steel bar stock. For the structure of this application it is contemplated that the frame member 25 may be made of a size on the order of the size of the roller shaft, say in the neighborhood of /2 inch round bar stock. It will be understood, of course, that the roller shaft 17 is tensioned to a point within its elastic limit. When a load on the conveyor belt 13 passes over roller 16, both the roller shaft 17 and frame member 25 will jointly accept it.

In my co-pending application, Serial No. 80,869, now Patent Number 3,109,534, the shock link 61 is illustrated and described. The same shock line illustrated and described in that application may be employed in this construction to great advantage. When employed, its effectiveness is unimpaired,

Further, in my co-pending application, Serial No. 80,869, filed January 5, 1961, now Patent Number 3,109,534, the training slot arrangement, illustrated best in FIGURES 3, 5 and 6, is illustrated. It will be understood that the present invention is not confined to any particular training arrangement. A training arrangement is illustrated here primarily to illustrate the fact that wing roller training arrangements may be utilized in conjunction with the tensioning feature.

When the extension member 45 is in the position illustrated in FIGURE 5, wing roller 16 will be positioned exactly transversely to the longitudinal axis of the conveyor and the training effect will be directed in a direction substantially perpendicular to the longitudinal axis of the roller. When the rounded portion 50 of nut 49 is placed in right seat 53, as illustrated in FIGURE 6, wing roller 17 will be canted inwardly in a downstream direction with respect to the longitudinal axis of the conveyor, all as illustrated by the arrows in FIGURE 6. In FIGURE 6, arrow T represents the direction of the training force which, it will be noted, is substantially perpendicular to the axis of the roller. Arrow X represents the direction of belt travel which coincides with the longitudinal axis of the conveyor. Again, it is not essential that the illustrated wing roller training arrangement be employed; any wing roller training arrangement will be effective so long as wing roller shaft 17 and frame member 25 may be simultaneously put under tension in the chosen training position.

Although a preferred embodiment of the invention has been illustrated, it should be clearly understood that various modifications and refinements will be readily apparent to those skilled in the art. Those equivalent embodiments and refinements are therefore to be considered within the purview of this description, and the scope of the invention is intended to be limited only by the scope of the following appended claims.

I claim:

1. A high strength, minimum weight, impact resistant roller assembly for use in a vertically flexible belt conveyor idler assembly, said roller assembly including in combination,

a shaft mounted belt supporting roller,

a supporting frame assembly for the roller, said frame assembly including,

an elongated, slightly bodily resilient frame member,

means for connecting the inner and outer portions of the resilient frame member to the inner and outer portions, respectively, of the roller shaft,

means for imparting tension directly to the roller shaft coincident with the shaft axis and thereby simultaneously stressing the bodily resilient frame member, and

means for connecting at least one end of the roller assembly to an adjacent roller assembly for flexing movement with respect thereto.

2. The roller assembly of claim 1 further characterized in that the elongated, slightly bodily resilient frame member has a Weight per unit length ratio on the order of the weight per unit length ratio of the roller shaft.

3. The roller assembly of claim 1 further characterized in that the means for placing the roller shaft under tension and simultaneously stressing the bodily resilient frame member is adjustable throughout at least a substantial portion of the elastic limit range of the elongated bodily resilient frame member.

4. The roller assembly of claim 2 further characterized in that the means for placing the roller shaft under tension is a threaded extension connectible, at its inner end, to the outer portion of the roller shaft, and a nut, the inner side of said nut engaging a generally upwardly projecting extension of the elongated resilient member and effective to place the shaft under tension when tightened.

5. An idler assembly for a flexible belt conveyor, said assembly including, in combination,

a plurality of roller assemblies, said plurality of roller assemblies being adjacent one another and including a Wing roller assembly at each end thereof, each wing roller assembly including,

a shaft mounted belt supporting roller and a supporting frame assembly for the roller, said frame assembly including an elongated, slightly bodily resilient frame member,

means for connecting the inner and outer portions of the resilient frame member to the inner and outer portions, respectively, of the roller shaft,

means for directly connecting the inner portion of each wing roller assembly to the adjacent end of an adjacent roller assembly which enables the roller assemblies to flex with respect to one another in a generally vertical plane,

and means for connecting each of the wing roller assemblies to an associated wire rope in a wire rope sideframe conveyor.

6. The idler assembly of claim 5 further characterized in that said last named means enables said roller assembly, and to a lesser degree the balance of the roller assemblies, to shift downstream in response to generally longitudinally directed impact loads.

7. An idler assembly for a flexible belt conveyor, said assembly including, in combination,

a plurality of roller assemblies, said plurality including a pair of wing roller assemblies flanking at least one intermediate roller, each of said wing roller assemblies including,

a shaft mounted belt supporting roller and a supporting frame assembly for the roller, said frame assembly including,

an elongated, slightly bodily resilient frame member,

means for connecting the inner and outer portions of the resilient frame member to the inner and outer portions, respectively, of the roller shaft,

means for placing each wing roller shaft under tension and simultaneously stressing the associated bodily resilient frame member,

means for connecting the inner portion of each wing roller assembly to the adjacent end of an adjacent intermediate roller assembly which enables the roller assemblies to flex with respect to one another in a generally vertical plane, and

means for connecting each of the outermost roller assemblies to an associated wire rope in a wire rope sideframe conveyor.

8. The idler assembly of claim 7 further characterized in that means for connecting the inner portion of each resilient frame member to the inner portion of an associated roller shaft is a generally upwardly projecting support structure, the adjacent end of the adjacent intermediate roller assembly being pivotally connected to the support structure.

9. The idler assembly of claim 7 further characterized in that the means for connecting each of the outermost roller assemblies to an associated wire rope enables the roller assembly, and to a lesser extent the balance of the roller assemblies, to shift downstream in response to generally longitudinally directed impact loads.

10. The idler assembly of claim 9 further characterized in that the connecting means are shock link assemblies pivotally connected at one end to an associated wire rope clamp and at their other end to an associated roller wing assembly.

11. A Wire rope sideframe belt conveyor, said conveyor including, in combination,

a pair of generally parallel wire ropes trained along a conveying course,

means for supporting and maintaining the ropes generally parallel to one another along the course,

a plurality of return idlers for supporting the return reach of a conveyor belt, and

a plurality of carrying idlers for supporting the conveying reach of a conveyor belt, at least one of said carrying idlers including, in combination,

a plurality of roller assemblies, said plurality including a pair of wing roller assemblies, each wing roller assembly including a shaft mounted belt supporting roller and a supporting frame assembly for the wing roller, said frame assembly including an elongated, slightly bodily resilient frame member,

means for connecting the inner and outer portions of the resilient frame member to the inner and outer portions, respectively, of the roller shaft,

means for connecting the inner portion of each wing roller assembly to the adjacent end of an adjacent roller assembly which enables the roller assemblies to flex with respect to one another in a generally vertical plane,

and means for connecting each of the wing roller assemblies to an associated wire rope.

Kendall Oct. 12, 1937 Madeira Nov. 25, 1952 

1. A HIGH STRENGTH, MINIMUM WEIGHT, IMPACT RESISTANT ROLLER ASSEMBLY FOR USE IN A VERTICALLY FLEXIBLE BELT CONVEYOR IDLER ASSEMBLY, SAID ROLLER ASSEMBLY INCLUDING IN COMBINATION, A SHAFT MOUNTED BELT SUPPORTING ROLLER, A SUPPORTING FRAME ASSEMBLY FOR THE ROLLER, SAID FRAME ASSEMBLY INCLUDING, AN ELONGATED, SLIGHTLY BODILY RESILIENT FRAME MEMBER, MEANS FOR CONNECTING THE INNER AND OUTER PORTIONS OF THE RESILIENT FRAME MEMBER TO THE INNER AND OUTER PORTIONS, RESPECTIVELY, OF THE ROLLER SHAFT, MEANS FOR IMPARTING TENSION DIRECTLY TO THE ROLLER SHAFT COINCIDENT WITH THE SHAFT AXIS AND THEREBY SIMULTANEOUSLY STRESSING THE BODILY RESILIENT FRAME MEMBER, AND MEANS FOR CONNECTING AT LEAST ONE END OF THE ROLLER ASSEMBLY TO AN ADJACENT ROLLER ASSEMBLY FOR FLEXING MOVEMENT WITH RESPECT THERETO. 